Pressure is mounting on Senate Majority Leader Mitch McConnell to name a select committee to investigate reports of election-related Russian cyberattacks. But his first instinct was correct: The inquiry should be done by the Senate and House Intelligence Committees.

Over the weekend, Sens. John McCain and Lindsey Graham became the first Republicans to urge the rarely used “select committee” route.

Congress last did that with the House probe of the 2012 terrorist attack at Benghazi — an effort Democrats loudly denounced as a partisan witch hunt. Are they now looking to even the score?

McCain and Graham say such a committee is “justified by the extraordinary scope and scale of the cyber problem.” But the two Intelligence Committees are well-versed in national security matters — and there’s nothing to suggest they can’t handle it themselves.

The danger with a select committee is that it becomes a self-sustaining political machine — and a prime opportunity for partisan grandstanding.

Yes, McCain genuinely believes Russian cyberattacks represent a threat. But Democrats’ motives clearly include an interest in undermining the president-elect’s legitimacy and distracting from his agenda.

Team Trump’s caustic skepticism on the whole issue is overdone. But it’s clearly reacting to the sense that recent reports on the hack attacks — unconfirmed news stories from Democratic sources — are aimed largely at undermining Donald Trump’s victory. Why won’t the CIA send anyone to testify before Congress on the issue?

Most important: Even McCain maintains that the hacking didn’t shift the results. No voting machines were attacked or votes altered. Vladimir Putin did not cost Hillary Clinton the presidency.

Congress does indeed owe it to the American people to fully investigate what happened — and why the Obama administration took no action. But it needs to be done fairly and even-handedly — and the Intelligence Committees are the best vehicle for that.